Online-only consoles make no sense.
Online-only devkits make perfect sense, given that every gen some end up in unauthorized hands and stuff gets leaked.
If I were making a devkit for a console, I'd make sure it phoned home and reported its IP address every few minutes, and if it couldn't reach home after a while it would lock itself down.
Of course, if I did such a thing, and didn't explain everything to developers, some of them would probably jump to conclusions as to what that means about the production platform.
Microsoft wouldn't be doing this if there wasn't some sort of accord with EA, Activision, and SONY as well.
Fixed.
The offline gamer is useless to MS.
They won't pay for XBL. They won't buy XBLA games. They won't buy video content. They won't buy DLC. They won't subscribe to Random MS Service #7.
From MS's perspective offline users cost MS money (assuming the new Xbox is sold at a loss).
So why would MS support offline gamers? It doesn't make sense to their financial desires.
What a load of shit. Microsoft makes ten bucks off every third-party disc sold, and we are talking everything from Call of Duty to Need for Speed. And much more money per disc on profitable first-party games like Halo and Forza. The revenue generated by the offline 360 gamer has to be in billions of dollars at this point. They aren't going to walk away from that, it isn't going to happen. Microsoft didn't get to where they are today by leaving billions of dollars on the table.